Manufacturers of mechanical equipment, food packagers and other packagers, and other users of wax for lubricating, sealing, and other uses have a continuing need for high quality wax compositions. In certain uses, a heavy wax is needed. The quality requirements increase regularly.
Manufacturing a high quality wax composition that meets more stringent requirements is typically more expensive than manufacturing a wax composition meeting less stringent requirements. This may be due to both a higher priced feed to such a process and additional or more expensive processing involved in such manufacturing.
It would be advantageous to have a relatively inexpensive process for producing heavy wax compositions. Such a process would ideally utilize a readily available inexpensive feedstock. Waste plastics/polymers have been used in known processes for the manufacture of some synthetic hydrocarbons, typically fuels or other polymers.
According to the latest report from the Office of Solid Waste, USEPA, about 62% of plastic packaging in the U.S. is made of polyethylene, the preferred feed for a plastics to waxes process. Equally important, plastics waste (after recycling) is the fastest growing waste product with about 18 million tons/yr in 1995 compared to only 4 million tons/yr in 1970. This presents a unique opportunity, not only to acquire a useful source of high quality heavy wax, but also address a growing environmental problem at the same time.
EP patent application 0620264A2 discloses a process for making a lube oil from waste plastics. The process utilizes a cracking process in a fluidized bed of inert solids and fluidized with, e.g., nitrogen. The product of the cracking is hydrotreated over an alumina catalyst or other refractory metal oxide support containing a metal component, and then optionally catalytically isomerized. EP 0620264A2 does not teach a process of producing a high yield of heavy waxes.
It would be advantageous to have a process using readily available waste plastics to produce a high yield of wax compositions, especially heavy wax compositions. The process of the present invention meets this need.